I don't see anyone saying that women need to be 'chaperoned' and think some of this extrapolation is in your head Offred and is just projection because of what's going on in your own life at the moment.
I also fundamentally disagree that the problem is always The Relationship.
If someone wants to make one of his friendships sexual, the problem is with That Individual and his own personal boundaries. And that crisis affects a very broad range of people in all sorts of different relationships, from the serial shaggers and liars - to the man or woman who is in a content marriage or relationship, has no urge to have an affair but who imperceptibly allows a friendship to cross the line. The people in that latter camp delude themselves as much as their concerned partners, insisting that they feel 'only friendship' for this person who's leaning on them heavily and because contrary to what some folk are saying the cultural default is for people to be 'cool' about opposite-sex friendships, some men and women fear being seen as controlling and possessive more than they fear the burgeoning affair that's going on right under their noses.
The 'pragmatism' I referred to again relates to Individuals and I made that very clear. Any individual who blithely thinks he is immune from an ego boost when someone else finds him attractive is not being pragmatic at all. He is being delusional, both to himself and his partner. The people who know themselves very well indeed and don't beat themselves up for finding another person attractive, or worse beat their marriage up and assume it must be faulty if they do, have good boundaries and swerve friendships with people where there is an intense mutual attraction. Again, this is about that individual and his/her self-awareness and that's got fuck all to do with The Relationship.
I agree there's just no point policing another person's activity, but that doesn't mean that a partner has got to sit quietly by and Suck It Up, or refrain from saying a situation makes her uncomfortable. If the Individual she's married to is reasonable and self-aware, he might say 'You know, you're right - this is getting a bit close for comfort and I am getting a bit too involved with this person. I'd feel the same if this was you' whereas a Nice Man who Self-Deludes will say 'Sure she's attractive and good company, but we are Just Friends' (and carry on) and a Complete Arsehole will say 'I'll see who I want when I want and I won't take any orders from you'.
If everyone who had an affair with a 'friend' presented in daily life as a Complete Arsehole, life would be much simpler for his partner.
But people who have affairs with 'friends' are often a lot more nuanced and complex than that and their partners are the ones I'm thinking of when I read your dismissive, intensely self-focusing posts.
I'd hate it if there was even one poster married to a decent bloke who's crossing the line, who felt as a result of your posts that she should shut the fuck up and suppress all her instincts that danger is present.